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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

YAKUTAT BAY GLACIERS                                     25
between Canada and Alaska turns northward. The bay pierces first a low foreland occupied by the ice plateau of Malaspina Glacier on the west side, but on the southeast side composed of moraines and glacial gravels deposited during a former expansion of the Yakutat Bay and Russell Fiord glaciers. It then cuts across the low front range of mountains to the base of the lofty, snow-covered peaks of the St. Elias Range. It turns twice at high angles, and parallels itself back to the foreland, the distance from the mouth of the bay to its head being fully 75 miles.
The name Yakutat Bay is now applied only to the outer part of the inlet (PI. I, A), mainly outside the mountain front, and throughout most of its extent bordered by a low coast, the wooded foreland on the southeast, the gravel fans and sandy beaches with strips of forest on the west, and behind these the moraine-covered ice bank which forms the outer border of Malaspina Glacier. This bay, which is 20 miles wide at the mouth, narrows progressively toward the head and, about half way between the mouth and head, the mountains approach to form the southeastern shore. At the head of the outer bay the mountains also converge from the west, and here the bay narrows to 8 miles. From this point, where the mountains form both shores of the inlet, on to the first bend the name Disenchantment Bay is applied. It is walled in by mountains rising abruptly from the sea to elevations of 2000 or 8000 feet and is a true fiord, with roughly parallel walls and a width of from 2 to 4 miles. The name of the bay again changes where it bends abruptly at an acute angle, from here on to the head of the inlet being called Russell Fiord. Excepting at its very head this portion of the inlet is also a mountain-walled fiord with a width of from 1 to 8 miles. Where the northwestern arm of Russell Fiord bends slightly, at Cape Enchantment, the fiord bifurcates, one arm extending southward as the southeast arm of Russell Fiord, the other extending eastward as Nunatak Fiord.
With the exception of the irregular coast line of the foreland on the southeast shore of outer Yakutat Bay, and of the head of Russell Fiord, also in the foreland, the inlet, throughout almost its entire extent, has a generally straight coast line. There are a few small projecting points and a few small bays, but, although there are many valleys tributary to the inlet, the mouths of most of them are above the level of the fiord waters so that there are few bays. There are only two notable exceptions to this statement, Nunatak Fiord, at the head of which stands the ice cliff of Nunatak Glacier, and Seal Bay in the valley of which lies Hidden Glacier whose glacial streams have deposited an extensive outwash gravel plain, thereby greatly shortening this indentation. Were Hubbard Glacier to recede notably, there would doubtless be still other irregularities in the bay at the bend where Disenchantment Bay and Russell Fiord unite. The interpretation of these features, which are due to the erosive work of formerly expanded glaciers, may for the present be postponed.
The straight coast line which Yakutat Bay indents is a coastal plain built by glacial deposit, and mainly by glacial stream deposit, but worked over, in its outer portion at least, by the ocean waves which are ever beating upon its margin exposed to the open Pacific.1 To the southeast of Yakutat Bay this coastal plain is still in process of active outbuilding, for numerous large glaciers descend from the mountains and spread out upon it at the mountain base, with huge glacial streams issuing from their fronts and flowing in braided courses across it; but these glaciers are evidently shrunken, and the
i Blackwdder, E., Amer. Journ. Sci., Vol. XXVII, 1909, pp. 459-466.